I have been fighting this issue for the past few years. My gunite pool was built in 2013.
I have Black Onyx plaster.
I have been using the TFP - BBB method of managing pool chems for a few years and feel I am knowledgeable in chem management.
So I have been getting these small white calcium specs on the walls and floors of the plaster (maybe 2-3 in a 12'-18" square area). I use a good SS brush and that seems to keep them almost dissolved or removed ... but never completely. If I don't brush for a week - they "grow" larger in size ... I can almost rub them off by hand as they are soft.
I have been good at keeping my CSI levels on a slight negative base ... -.1 to -.3 in the hope that the negative base will "pull" the extra calcium and prevent scaling .
I don't have scaling at the tile water line ... just on the walls/floor.
Chems ....
FC - 4.0 (I keep it between 3-5)
PH - 7.8
ALK - 35 (it has been low this spring and I am trying to raise it to 50 (plain bulk baking soda). Have gotten as high as 40-45 but it falls back to 35ish. Have only started adding the BS in the past few weeks - maybe 30# total. Don't have any aerating factors (waterfalls etc)
CH - 150-160
CYA - 55
Salt - 3400
Any ideas would be appreciated.
PS ... I drain my pool (20K) every 2 years and power wash the small white calcium/scale deposits from the walls/floors - looks really good for the first couple of months (April/May) then the white spot buildup starts again.
Thanks!
I have Black Onyx plaster.
I have been using the TFP - BBB method of managing pool chems for a few years and feel I am knowledgeable in chem management.
So I have been getting these small white calcium specs on the walls and floors of the plaster (maybe 2-3 in a 12'-18" square area). I use a good SS brush and that seems to keep them almost dissolved or removed ... but never completely. If I don't brush for a week - they "grow" larger in size ... I can almost rub them off by hand as they are soft.
I have been good at keeping my CSI levels on a slight negative base ... -.1 to -.3 in the hope that the negative base will "pull" the extra calcium and prevent scaling .
I don't have scaling at the tile water line ... just on the walls/floor.
Chems ....
FC - 4.0 (I keep it between 3-5)
PH - 7.8
ALK - 35 (it has been low this spring and I am trying to raise it to 50 (plain bulk baking soda). Have gotten as high as 40-45 but it falls back to 35ish. Have only started adding the BS in the past few weeks - maybe 30# total. Don't have any aerating factors (waterfalls etc)
CH - 150-160
CYA - 55
Salt - 3400
Any ideas would be appreciated.
PS ... I drain my pool (20K) every 2 years and power wash the small white calcium/scale deposits from the walls/floors - looks really good for the first couple of months (April/May) then the white spot buildup starts again.
Thanks!
